The present embodiments are directed to a conveyor sluice system useful for recovering fine particles of target materials from a feed stream of less heavy particles.
A water feed stream is a commonly used to mine/separate gold or other target minerals from bulk earth. Bulk earth is generally comprised of precious metals, minerals, bulk rock (primarily composed of silicate-based materials), organic matter, etc. Feed stream mining is considered an effective way to capture target particles (gold/minerals) that are larger than 100 μm. Target particles that are less than 100 μm are generally considered cost prohibitive to recover and are, accordingly, discarded as waste or tailings.
It is to innovations related to this subject matter that the claimed invention is generally directed.
The present embodiments are generally directed to a conveyor sluice system useful for mining fine target particles (silt) that would otherwise be discarded as tails from a feed stream. As used herein, fine target particles are considered to be particles that are a) smaller than 100 μm when granules (3D grains) or b) potentially larger than 100 μm when the particles are platelet/sheet-like in shape (essentially 2D) that do not easily settle in water.
Some embodiments of the present invention contemplate a method for segregating conveyor sluice slurry using a conveyor sluice that comprises a textured belt wrapped around a head pulley roller and tail pulley roller. The belt defining a textured outer surface that when facing upward (towards the sky) is considered a sky-facing belt surface and when facing downward (towards the ground) is considered a ground-facing belt surface. The conveyor sluice can be positioned at a conveyor sluice angle between −5° and −45° from a horizontal plane. Conveyor sluice slurry can be introduced to the sky-facing belt surface approximately at the head pulley roller (which is more or less at the highest point of the conveyor belt). The sky-facing belt surface can be made to essentially continuously move towards the head pulley roller while continuously flowing the conveyor sluice slurry towards the tail pulley roller. While the sky-facing belt surface is essentially continuously moving towards the head pulley roller, a concentrated aggregate is separated out from the conveyor sluice slurry. The concentrated aggregate settles in grooves in the textured outer surface. While the sky-facing belt surface is essentially continuously moving towards the head pulley roller, the textured outer surface is rotated over the head pulley roller. The concentrated aggregate is then sprayed off the textured belt surface, or more specifically out from the grooves with rinse water at the head pulley roller and/or the ground-facing surface. The rinse water and the sprayed off concentrated aggregate is collected in a concentrate launder where the concentrated aggregate along with the rinse water is pumped from the concentrate launder to a decanting hopper. The concentrated aggregate and at least a portion of the rinse water in the decanting hopper is emptied to a finishing table. This can be a continuous process whereby the finishing table constantly receives concentrated aggregate along with rinse water from the decanting hopper. Accordingly, the decanting hopper constantly receives the concentrated aggregate along with the rinse water from the concentrate launder, which receives a continuous supply of concentrated aggregate from the constantly moving belt.
Yet another embodiment of the present invention contemplates a conveyor sluice arrangement comprising a belt defined by a textured outer surface, wherein the belt is wrapped around (and in tension between) a head pulley roller and a tail pulley roller. At any given time, the textured outer surface comprises a sky-facing portion, a ground-facing portion, an upper in-transition portion or a lower in-transition portion (where the belt cooperates with the pulley rollers). The conveyor sluice defines a sluice length as extending from the head pulley roller to the tail pulley roller. A conveyor sluice width is defined as greater than or equal to a belt width of the belt. The conveyor sluice is at an angle that is between −5° and −45° from a horizontal plane, wherein the conveyor sluice angle is defined by the sky-facing portion between the head pulley roller and the tail pulley roller. The head pulley roller is above the tail pulley roller. A post hydrocyclone aggregate distributor feeds conveyor sluice slurry onto the sky-facing portion within 12 inches of the head pulley roller. At least one belt cleaning rinse nozzle (with rinse water) is directed at the textured outer surface either at the upper in-transition portion at the head pulley roller or at the ground-facing portion. A concentrate launder is located under the ground-facing portion to collect the rinse water containing the fine material (from the conveyor sluice slurry) trapped in the belt grooves/textured outer surface. A concentrate pump is in communication with the concentrate launder and a concentrate hopper to move the rinse water and fine material to the concentrate hopper. A belt motor configured to drive the sky-facing portion only towards the head pulley roller at a velocity, which in certain embodiments is adjustable. Some embodiments contemplate the velocity being between 1-30 feet per minute.
Still other certain embodiments of the present invention contemplate a mineral recovering system comprising a static riffle sluice defined by a riffle sluice leading edge and a riffle sluice trailing edge. The static riffle sluice configured to receive a raw feed slurry from a grizzly hopper. An aggregate screen, disposed downstream from the riffle sluice trailing edge, that essentially permits only screened undersized aggregate from the raw feed slurry to pass to an undersized aggregate collecting tank. A static hydrocyclone is configured to receive the screened undersized aggregate. The mineral recovery system further comprises at least one conveyor sluice having a textured belt that wraps around a head pulley roller and a tail pulley roller, the head pulley roller is positioned higher than the tail pulley roller. The textured belt is configured to rotate with a sky-facing belt portion moving towards the head pulley roller and a ground-facing belt portion moving towards the tail pulley roller. Post hydrocyclone aggregate is received from the static hydrocyclone, which is configured to be distributed on the sky-facing surface of the belt within 12 inches of the head pulley roller. The textured belt is configured to retain a concentrated aggregate. At least one belt cleaning rinse nozzle is directed at the textured belt within 12 inches of the head pulley roller but not directed at the sky-facing belt surface. The belt cleaning rinse nozzle is configured to spray rinse water on the textured belt to liberate the concentrated aggregate from the textured belt. A finishing table is configured to receive the liberated concentrated aggregate and separate fine target material from the concentrated aggregate.
Initially, this disclosure is by way of example only, not by limitation. Thus, although the instrumentalities described herein are for the convenience of explanation, shown and described with respect to exemplary embodiments, it will be appreciated that the principles herein may be applied equally in other similar configurations involving mining. The phrases “in one embodiment”, “according to one embodiment”, and the like, generally mean the particular feature, structure, or characteristic following the phrase, is included in at least one embodiment of the present invention and may be included in more than one embodiment of the present invention. Importantly, such phases do not necessarily refer to the same embodiment. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic. As used herein, the terms “having”, “have”, “including” and “include” are considered open language and are synonymous with the term “comprising”. Furthermore, as used herein, the term “essentially” is meant to stress that a characteristic of something is to be interpreted within acceptable tolerance margins known to those skilled in the art in keeping with typical normal world tolerance, which is analogous with “more or less.” For example, essentially flat, essentially straight, essentially on time, etc. all indicate that these characteristics are not capable of being perfect within the sense of their limits. Accordingly, if there is no specific+/−value assigned to “essentially”, then assume essentially means to be within +/−2.5% of exact. In what follows, similar or identical structures may be identified using identical callouts.
Some embodiments of the present invention are directed to a conveyor sluice system useful for mining fine particles of target materials (e.g., recovering target minerals) that are heavier than silicon and other bulk earth. Bulk earth is generally comprised precious metals, rare or heavy element minerals, bulk rock primarily composed of silicate based molecules, organic matter, etc. Certain aspects of the present invention are directed to mining for gold or other metallic elements or minerals that are heavier than bulk earth using water as a carrier using a conveyor sluice system. Several conveyor sluice embodiments can comprise a belt defined by a textured outer surface wherein the belt is wrapped around a head pulley roller and a tail pulley roller. A post hydrocyclone aggregate distributor feeds conveyor sluice slurry onto the top of the belt near or optionally within 12 inches of the head pulley roller. As the conveyor sluice slurry flows down the belt texture surface, concentrated aggregate (rich in target heavy minerals, such as gold, silver or tin, for example) settles and gets caught in the belt texture. At least one belt cleaning rinse nozzle aims rinse water at the textured outer surface at an in-transition portion of the belt that wraps around the head pulley roller and sprays the concentrated aggregate off the belt surface and out from the texture. A concentrate launder located under the ground-facing portion of the belt collects the rinsed off concentrated aggregate and pumps it to a concentrate hopper. The concentrated aggregate is separated at a finishing table to produce the final heavy mineral sought after. Certain other embodiments envision an apparatus similar to the embodiments shown in the figures below but used for reclaiming precious metals from trash. This is considered urban mining herein.
In the present embodiment of
An aggregate screen 110, located near or after the riffle sluice trailing edge 124, is used to separate out the oversized aggregate (not shown) from the feed slurry 112. The oversized (course) aggregate passes over the aggregate screen 110 and down the screen oversize shoot 108 where it can be carted away as waste, also known as tailings. The screened feed slurry 111, which is essentially the water and undersized aggregate, is channeled to and retained in an undersized aggregate screen tank 120. The screened feed slurry 111 is depicted with a dashed-line oval around it representing that the screened feed slurry 111 is actually in the tank 120. An undersized aggregate pump 126 pumps the post screened undersized feed slurry (undersized aggregate and water) 111 to a hydrocyclone 115 by way of a hydrocyclone inlet pipe 118. Certain embodiments envision the undersized aggregate being less than ⅛ of an inch in diameter. The mouth of the inlet pipe 119 is positioned tangentially and in-line with a downward ramping channel within/inside of the hydrocyclone 115, which segregates the undersized aggregate (from the screened feed slurry 111) into heavier post hydrocyclone aggregate (not shown). The heavier post hydrocyclone aggregate flows out of the hydrocyclone underflow port 117 into a conveyor-sluice distributor tank 114. Though still a slurry, the heavier post hydrocyclone aggregate comprises less water because the bulk of the water along with the lighter undersized aggregate in the hydrocyclone 115 flows to the top of the hydrocyclone 115 and out the hydrocyclone overflow pipe 116 as tailings. The post hydrocyclone aggregate flows down the conveyor sluice distributor pathway 134, which in this case is a pipe, and onto at least one conveyor sluice 200.
For reference,
In operation, the heavier undersized aggregate from the hydrocyclone 115 (in the conveyor sluice distributor tank 114) is dispersed via the conveyor sluice slurry distributor 262 at or near the conveyor leading edge 242, as shown. The conveyor leading edge 242 is defined approximately where the head pulley roller 204 is located on the conveyor sluice 200 and the conveyor trailing edge 240 is defined approximately where the tail pulley roller 202 is located. Certain embodiments envision the conveyor sluice slurry distributor 262 dispensing the post hydrocyclone aggregate within 12 inches of the conveyor leading edge 242 on the sky-facing portion of the conveyor belt 252 of the textured outer surface 216. Certain embodiments envision the post hydrocyclone aggregate mixed with water to create conveyor sluice slurry 228, while other embodiments envision the post hydrocyclone aggregate already containing sufficient water from the hydrocyclone 115, which essentially makes up the conveyor sluice slurry 228.
As shown in this embodiment, the conveyor sluice slurry 228 is spread evenly across the belt width 207 (shown in
As the sky-facing portion 252 of the conveyor belt 210 moves (is rotated) 226 towards the conveyor sluice leading edge 242, the heavy concentrated aggregate 300 that is retained/trapped in the belt texture 216 is carried under the conveyor sluice slurry distributor 262 and over the upper in-transition portion 258 defined by the belt 21 going over the head pulley roller 204, as shown in
In certain embodiments, the conveyor sluice slurry 228 moves down the textured outer surface 216 towards the conveyor sluice trailing edge 240 essentially in a laminar flow stream. ‘Essentially’ as applied to the laminar flow herein is envisioned as the flow stream of the conveyor sluice slurry 228 possibly having small amounts of turbulence including micro-turbulent eddies at the boundary layer of the textured outer surface 216. Laminar flow, and in some cases moderately turbulent flow has an advantage of producing flow stratification that enhances movement of the heavy concentrated aggregate 300 to the belt texture 212 (of
Certain other embodiments of the conveyor sluice of
With the present description in mind, below are some examples of certain embodiments illustratively complementing some of the methods and apparatus embodiments to aid the reader. The elements called out below in view of the various figures are examples provided to assist in understanding the present invention and accordingly should not be considered limiting.
In that light, as depicted in
The mineral recovery system embodiment 100 further envisioning the stationary riffle sluice 105 residing at a riffle sluice angle α 235 between −5° and −45° from a horizontal reference plane 230.
The mineral recovery system embodiment 100 further imagining wherein the static hydrocyclone 115 is further configured to receive water (not shown) with the screened undersized aggregate (not shown).
The mineral recovery system embodiment 100 further pondering the conveyor sluice 200 having a conveyor sluice angle α 235, defined along the sky-facing belt surface 252 from the head pulley roller 204 to the tail pulley roller 202, being between −5° and −45° from the horizontal plane 230.
The mineral recovery system embodiment 100 wherein the aggregate screen 110 blocks essentially all course aggregate (not shown) that is larger than ⅛ of an inch from the feed slurry 112.
The mineral recovery system embodiment 100 further comprising an undersized aggregate pump 126 disposed between the riffle sluice tank 120 and the hydrocyclone 115, the undersized aggregate pump 126 configured to move the screened undersized aggregate (not shown) to the hydrocyclone 115.
The mineral recovery system embodiment 100 further comprising a conveyor sluice distribution pathway 134 that channels the post hydrocyclone aggregate (not shown) from the hydrocyclone 115 to the textured belt 210.
The mineral recovery system embodiment 100 further comprising at least one laminar flow water nozzle 310 configured to direct conveyor sluice slurry 228 at the sky-facing belt surface 252 within 12 inches of the head pulley roller 204. A reject material trough 208 can be located vertically below the tail pulley roller 202 (in the direction of the arrow 234 of
The mineral recovery system embodiment 100 further comprising a concentrate launder 308 configured to collect the concentrated aggregate 300 and the rinse water 304. This embodiment can further comprise a slurry/concentrate pump (not shown) that pumps the concentrated aggregate 300 and the rinse water 304 into a decanting hopper 130 that is above the concentrate launder 308 (again in the vertical direction defined by the arrow 233 of
The mineral recovery system embodiment 100 further envisioned to comprise a primary scalping screen (not shown) that filters or otherwise scalps large raw aggregate (not shown) from the feed slurry 112 prior to the feed slurry 112 reaching the stationary riffle sluice 105.
Yet another embodiment contemplates a conveyor sluice embodiment 200 comprising a belt 210 defined by a textured outer surface 216 wherein the belt 210 is wrapped around a head pulley roller 204 and a tail pulley roller 202. At any given time, the textured outer surface 216 comprises a sky-facing portion 252, a ground-facing portion 254 or an upper in-transition portion 258 while the belt 210 is cooperating with the pulley rollers 202 and 204. The conveyor sluice 200 defines a sluice length 205 as extending from the head pulley roller 204 to the tail pulley roller 202 and a conveyor sluice width 206 defined as greater than or equal to a belt width 207 of the belt 210. The conveyor sluice is at an angle 235 that is between −5° and −45° from a horizontal plane 230, the conveyor sluice angle 235 defined by the sky-facing portion 252 between the head pulley roller 204 and the tail pulley roller 202. The head pulley roller 204 is above the tail pulley roller 202. A post hydrocyclone aggregate distributor 134 feeds conveyor sluice slurry 228 onto the sky-facing portion 252 within 12 inches of the head pulley roller 204. At least one belt cleaning rinse nozzle 302 (with rinse water 304) is directed at the textured outer surface 216 either at the upper in-transition portion 258 at the head pulley roller 204 or at the ground-facing portion 254. A concentrate launder 308 is located under the ground-facing portion 254. A concentrate pump 244 is in communication with the concentrate launder 308 and a concentrate hopper 130. A belt motor 238 configured to drive the sky-facing portion 252 only towards the head pulley roller 204 at a velocity 226, which in certain embodiments is adjustable. Some embodiments contemplate the velocity 226 being between 1-30 feet per minute.
The conveyor sluice embodiment 200 further contemplating wherein the sluice length 205 is longer than 6 feet.
The conveyor sluice embodiment 200 further envisioning wherein the head pulley roller 204 has a diameter that is between 3-16 inches and a length that at least spans a belt width 207.
The conveyor sluice embodiment 200 further imagining wherein the belt width 207 is at least 15 inches wide.
The conveyor sluice embodiment 200 further pondering wherein a substantial portion of the textured outer surface 216 is essentially always exposed to the outside environment 136. By substantial, it is meant and defined as more than 75% of the textured outer surface 216 is always exposed to the outside environment 136.
The conveyor sluice embodiment 200 further considering wherein the belt 210 is in tension caused by the head pulley roller 204 and the tail pulley roller 202.
The conveyor sluice embodiment 200 wherein the belt motor 238 drives at least one of the pulleys 202 and 204. The belt motor 238 drives the belt 210, which in certain embodiments can be adjusted to alter a rotational speed whereby an end user can select a ‘mass pull’ from 0 up to 40%. ‘Mass pull’ is defined as the amount of concentrated aggregate 300 that is trapped in the belt texture 216.
The conveyor sluice embodiment 200 further comprising a reject material trough residing below the tail pulley roller.
The conveyor sluice embodiment 200 wherein the belt 210 comprises raised side borders 220 that are located on either side of the belt 210, the raised side borders 220 extend outwardly 221 from the belt 210 further than the textured outer surface 216. The raised boarders 220 confine the fine material (from the conveyor sluice slurry 228) to be trapped in the belt texture 212.
The conveyor sluice embodiment 200 further comprising at least one particle suppression mister 236 that is aimed at the sky-facing portion 252, the mister 236 comprising a target area that is completely across the belt width 207 and at least partially along the sluice length 205.
The conveyor sluice embodiment 200 further comprising a slurry distributor 262 approximately at an interface defined where the head pulley roller 204 meets the belt 210.
The conveyor sluice embodiment 200 further comprising a belt vibration generator 264 that generates amplitude waves at between 1-400 Hz. The belt vibration generator 264 can optionally contact the belt 210 at the ground-facing portion 254 translating the belt vibration to the sky-facing portion 252.
The conveyor sluice embodiment 200 further envisioning wherein the vibration is adjustable via a sweep frequency. The vibration amplitude can be between 0.1-2.0 Gs. A g-force is a measure of acceleration known as the force of gravity. 1G is the acceleration of gravity generally has a value of 9.806 m/s2 or 32.1740 f/s2.
The conveyor sluice embodiment 200 further comprising a belt side rail 214 that is on either side of the belt sky-facing portion 252, which extends at least 0.75 inches from the textured outer surface 216. The belt side rails 214 confine the conveyor sluice slurry 228 to flow over the sky facing belt surface 252 and ultimately channeling the slurry stream 228 (i.e., the portion of the slurry 228 not trapped by the belt texture 212) into the reject material trough 208.
The conveyor sluice embodiment 200 further pondering the textured outer surface 216 comprising a pattern of 0.15-inch grooves 212 with 0.25-inch periods.
The conveyor sluice embodiment 200 further considering the conveyor sluice angle 235 being adjustable. Optional embodiments contemplate the conveyor sluice 200 being alongside a second conveyor sluice 200B that is essentially identical to the conveyor sluice 200 but is adjusted at a different conveyor sluice angle 235. In other words, a first conveyor sluice 200A is at a different angle than a second conveyor sluice 200B, as shown in
Still other embodiments contemplate a method for segregating conveyor sluice slurry 228 comprising providing a conveyor sluice 200 that comprises a textured belt 210 wrapped around a head pulley roller 204 and tail pulley roller 202. The belt 210 defining a textured outer surface 216 that when facing upward 221 is considered a sky-facing belt surface 252 and when facing downward is considered a ground-facing belt surface 254. The conveyor sluice can be positioned at a conveyor sluice angle 235 between −5° and −45° from a horizontal plane 230. Conveyor sluice slurry 228 can be introduced to the sky-facing belt surface 252 approximately at the head pulley roller 204. The sky-facing belt surface 252 can be made to essentially continuously move towards the head pulley roller 204 while continuously flowing the conveyor sluice slurry 228 towards the tail pulley roller 202. While the sky-facing belt surface 252 is essentially continuously moving towards the head pulley roller 204, a concentrated aggregate 300 is separated out from the conveyor sluice slurry 228. The concentrated aggregate 300 settles in grooves 212 in the textured outer surface 216. While the sky-facing belt surface 252 is essentially continuously moving towards the head pulley roller 204, the textured outer surface 216 is rotated over the head pulley roller 204. The concentrated aggregate 300 is then sprayed off of the textured belt surface 216, or more specifically, out from the grooves 212 with rinse water 304 (of
The above sample embodiments should not be considered limiting to the scope of the invention whatsoever because many more embodiments and variations of embodiments are easily conceived within the teachings, scope and spirit of the instant specification.
It is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with the details of the structure and function of various embodiments of the invention, this disclosure is illustrative only, and changes may be made in detail, especially in matters of structure and arrangement of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. For example, computer systems and controllers can be used to control the speed of the conveyor belt motors, the conveyor belt angles, the pumping rates in different locations in the system 100, etc., while keeping in sync with the scope and spirit of the present invention. Another example envisions the belt texture including any number of different stages, going from one texture arrangement to a different texture arrangement in different locations on the belt whether lengthwise or widthwise to potentially enhance functionality without departing from the scope and spirit of the present invention. Further, the term “one” is synonymous with “a”, which may be a first of a plurality.
It will be clear that the present invention is well adapted to attain the ends and advantages mentioned as well as those inherent therein. While presently preferred embodiments have been described for purposes of this disclosure, numerous changes may be made which readily suggest themselves to those skilled in the art and which are encompassed in the spirit of the invention disclosed and defined in the appended claims.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63/169,468 entitled: CONVEYOR SLUICE SYSTEM, filed on Apr. 1, 2021.
Number | Date | Country | |
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63169468 | Apr 2021 | US |